Turbine engine component including an axially aligned skin core passage interrupted by a pedestal

ABSTRACT

A component for a turbine engine includes a fore edge connected to an aft edge via a first surface and a second surface. Multiple cooling passages are defined within the turbine engine component. A skin core passage is defined immediately adjacent the first surface, and at least one pedestal interrupts a flow path through the skin core passage.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with government support under contract numberFA8650-09-D-2923-0021 awarded by the United States Air Force. Thegovernment has certain rights in the invention.

TECHNICAL FIELD

The present disclosure relates generally to turbine engine components,such as blades and vanes, and more specifically to a turbine enginecomponent including an axially aligned skin core cooling passageinterrupted by at least one pedestal.

BACKGROUND

Gas turbine engines, such as those utilized in commercial and militaryaircraft, utilize a compressor section to draw air into a flow path, acombustor section to mix compressed air with a fuel and ignite themixture, and a turbine section to expand the resultant combustionproducts. The expansion of the resultant combustion products drives theturbine section to rotate, which in turn drives the compressor sectionto rotate.

As a result of the exposure to combustion products, components withinthe turbine section are subject to extreme heat. To prevent heat relatedfatigue and damage, the turbine components are actively cooled viainternal cooling flow paths. Frequently air, or another coolant, isexpelled from the internal cooling passages along the surface of theturbine engine component to create a film cooling effect on the exteriorsurface of the turbine engine component.

SUMMARY OF THE INVENTION

In one exemplary embodiment a turbine engine component includes a foreedge connected to an aft edge via a first surface and a second surface,a plurality of cooling passages defined within the turbine enginecomponent, a skin core passage defined immediately adjacent the firstsurface, and at least one pedestal interrupting a flow path through theskin core passage.

In another exemplary embodiment of the above described turbine enginecomponent, the at least one pedestal includes a plurality of pedestalsdistributed through the skin core passage.

In another exemplary embodiment of any of the above described turbineengine components, at least one pedestal in the plurality of pedestalsincludes a film cooling hole defined at least partially within thepedestal, the film cooling hole connecting one of the plurality ofcooling passages to the first surface.

In another exemplary embodiment of any of the above described turbineengine components, the at least one pedestal has an oblong cross sectionrelative to a turbine engine including the turbine engine component.

In another exemplary embodiment of any of the above described turbineengine components, each of the oblong cross sections includes a longestdiameter, and the longest diameter is aligned with an axis of theturbine engine.

In another exemplary embodiment of any of the above described turbineengine components, each of the oblong cross sections includes a longestdiameter, and the longest diameter is aligned with a radius of theturbine engine.

In another exemplary embodiment of any of the above described turbineengine components, each of the pedestals has a cross section along adirection of flow through the skin core passage, the cross section beingone of an oval, a triangle, a rhombus, an airfoil, and a circle.

In another exemplary embodiment of any of the above described turbineengine components, at least 80% of a coolant entering the skin corepassage exits the skin core passage at the aft edge.

In another exemplary embodiment of any of the above described turbineengine components, the skin core passage defines an axial coolant flowpath.

In another exemplary embodiment of any of the above described turbineengine components, the film cooling hole connects a first cooling airflow path internal to the turbine engine component to the first surface,and wherein the skin core passage receives cooling air from a secondcooling air flow path internal to the turbine engine component, andwherein the second cooling air flow path is a low pressure cooling airflow path relative to the first cooling air flow path.

In another exemplary embodiment of any of the above described turbineengine components, the one of the plurality of cooling passagesconnected to the first surface via the cooling hole has a higher coolingair pressure than a cooling air pressure of the skin core passage.

In another exemplary embodiment of any of the above described turbineengine components, the turbine engine component is one of a blade outerair seal, a combustor liner, a blade, and a vane.

In another exemplary embodiment of any of the above described turbineengine components, the blade is a blade in a second or later turbinestage.

In one exemplary embodiment a gas turbine engine includes a compressorsection, a combustor section fluidly connected to the compressor sectionby a flowpath, a turbine section fluidly connected to the combustorsection by the flowpath, at least one gas turbine engine componentexposed to a fluid passing through the flowpath. The at least one gasturbine engine component includes a first surface and a second surface,at least one cooling passage defined within the turbine enginecomponent, a skin core passage defined immediately adjacent the firstsurface, and at least one pedestal interrupting a flow path through theskin core passage, the at least one pedestal connecting an interiorsurface of the at least one cooling passage to the first surface.

Another exemplary embodiment of the above described gas turbine enginefurther includes a film cooling hole defined within the at least onepedestal, the film cooling hole providing a flow path between the atleast one cooling passage to the first surface.

In another exemplary embodiment of any of the above described gasturbine engines, the at least one cooling passage includes a firstcooling passage and a second cooling passage, and the at least onepedestal connects an interior surface of the first cooling passage tothe first surface.

In another exemplary embodiment of any of the above described gasturbine engines, the first cooling passage receives cooling air from afirst source, the second cooling passage receives cooling air from asecond source, and wherein the skin core passage receives cooling airfrom the second cooling passage.

In another exemplary embodiment of any of the above described gasturbine engines, the first cooling passage receives cooling air from afirst source, the second cooling passage receives cooling air from thefirst cooling passage, and the skin core passage receives cooling airfrom the second cooling passage.

An exemplary method for cooling a gas turbine engine component includespassing a cooling flow along a surface of the gas turbine enginecomponent through a skin core passage, and providing a cooling filmalong the surface through at least one cooling hole, the at least onecooling hole passing through a pedestal interrupting cooling flowthrough the skin core passage.

Another example of the above described exemplary method for cooling agas turbine engine component includes providing a cooling film along thesurface through the at least one cooling hole includes receiving air ata first end of the cooling hole from a cooling passage internal to thegas turbine engine component and passing the air to a second end of thecooling hole at an exterior surface of the gas turbine engine component.

These and other features of the present invention can be best understoodfrom the following specification and drawings, the following of which isa brief description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically illustrates an exemplary gas turbine engine.

FIG. 2 schematically illustrates a turbine engine component.

FIG. 3 schematically illustrates an isometric view of a second exampleturbine engine component, including hidden elements.

FIG. 4 schematically illustrates a cross section of the second exampleturbine engine component of FIG. 3.

FIG. 5A schematically illustrates a first alternate pedestal crosssectional shape for the second example turbine engine component.

FIG. 5B schematically illustrates a second alternate pedestal crosssectional shape for the second example turbine engine component.

FIG. 5C schematically illustrates a third alternate pedestal crosssectional shape for the second example turbine engine component.

FIG. 6 schematically illustrates an example Blade Outer Air Seal.

DETAILED DESCRIPTION OF AN EMBODIMENT

FIG. 1 schematically illustrates a gas turbine engine 20. The gasturbine engine 20 is disclosed herein as a two-spool turbofan thatgenerally incorporates a fan section 22, a compressor section 24, acombustor section 26 and a turbine section 28. Alternative engines mightinclude an augmentor section (not shown) among other systems orfeatures. The fan section 22 drives air along a bypass flow path B in abypass duct defined within a nacelle 15, while the compressor section 24drives air along a core flow path C for compression and communicationinto the combustor section 26 then expansion through the turbine section28. Although depicted as a two-spool turbofan gas turbine engine in thedisclosed non-limiting embodiment, it should be understood that theconcepts described herein are not limited to use with two-spoolturbofans as the teachings may be applied to other types of turbineengines including three-spool architectures.

The exemplary engine 20 generally includes a low speed spool 30 and ahigh speed spool 32 mounted for rotation about an engine centrallongitudinal axis A relative to an engine static structure 36 viaseveral bearing systems 38. It should be understood that various bearingsystems 38 at various locations may alternatively or additionally beprovided, and the location of bearing systems 38 may be varied asappropriate to the application.

The low speed spool 30 generally includes an inner shaft 40 thatinterconnects a fan 42, a first (or low) pressure compressor 44 and afirst (or low) pressure turbine 46. The inner shaft 40 is connected tothe fan 42 through a speed change mechanism, which in exemplary gasturbine engine 20 is illustrated as a geared architecture 48 to drivethe fan 42 at a lower speed than the low speed spool 30. The high speedspool 32 includes an outer shaft 50 that interconnects a second (orhigh) pressure compressor 52 and a second (or high) pressure turbine 54.A combustor 56 is arranged in exemplary gas turbine 20 between the highpressure compressor 52 and the high pressure turbine 54. A mid-turbineframe 57 of the engine static structure 36 is arranged generally betweenthe high pressure turbine 54 and the low pressure turbine 46. Themid-turbine frame 57 further supports bearing systems 38 in the turbinesection 28. The inner shaft 40 and the outer shaft 50 are concentric androtate via bearing systems 38 about the engine central longitudinal axisA which is collinear with their longitudinal axes.

The core airflow is compressed by the low pressure compressor 44 thenthe high pressure compressor 52, mixed and burned with fuel in thecombustor 56, then expanded over the high pressure turbine 54 and lowpressure turbine 46. The mid-turbine frame 57 includes airfoils 59 whichare in the core airflow path C. The turbines 46, 54 rotationally drivethe respective low speed spool 30 and high speed spool 32 in response tothe expansion. It will be appreciated that each of the positions of thefan section 22, compressor section 24, combustor section 26, turbinesection 28, and fan drive gear system 48 may be varied. For example,gear system 48 may be located aft of combustor section 26 or even aft ofturbine section 28, and fan section 22 may be positioned forward or aftof the location of gear system 48.

The engine 20 in one example is a high-bypass geared aircraft engine. Ina further example, the engine 20 bypass ratio is greater than about six(6), with an example embodiment being greater than about ten (10), thegeared architecture 48 is an epicyclic gear train, such as a planetarygear system or other gear system, with a gear reduction ratio of greaterthan about 2.3 and the low pressure turbine 46 has a pressure ratio thatis greater than about five. In one disclosed embodiment, the engine 20bypass ratio is greater than about ten (10:1), the fan diameter issignificantly larger than that of the low pressure compressor 44, andthe low pressure turbine 46 has a pressure ratio that is greater thanabout five (5:1). Low pressure turbine 46 pressure ratio is pressuremeasured prior to inlet of low pressure turbine 46 as related to thepressure at the outlet of the low pressure turbine 46 prior to anexhaust nozzle. The geared architecture 48 may be an epicycle geartrain, such as a planetary gear system or other gear system, with a gearreduction ratio of greater than about 2.3:1. It should be understood,however, that the above parameters are only exemplary of one embodimentof a geared architecture engine and that the present invention isapplicable to other gas turbine engines including direct driveturbofans.

A significant amount of thrust is provided by the bypass flow B due tothe high bypass ratio. The fan section 22 of the engine 20 is designedfor a particular flight condition—typically cruise at about 0.8 Mach andabout 35,000 feet. The flight condition of 0.8 Mach and 35,000 ft, withthe engine at its best fuel consumption—also known as “bucket cruiseThrust Specific Fuel Consumption (‘TSFC’)”—is the industry standardparameter of 1 bm of fuel being burned divided by 1 bf of thrust theengine produces at that minimum point. “Low fan pressure ratio” is thepressure ratio across the fan blade alone, without a Fan Exit Guide Vane(“FEGV”) system. The low fan pressure ratio as disclosed hereinaccording to one non-limiting embodiment is less than about 1.45. “Lowcorrected fan tip speed” is the actual fan tip speed in ft/sec dividedby an industry standard temperature correction of [(Tram ° R)/(518.7 °R)]̂0.5. The “Low corrected fan tip speed” as disclosed herein accordingto one non-limiting embodiment is less than about 1150 ft/second.

Multiple components within the turbine section 28 include internalcooling passages for active cooling. Cooling air is typically drawn fromthe compressor section 24, such as via a compressor bleed, and providedto the cooled turbine component. Turbine engine components exposed tothe hottest temperatures, such as turbine vanes in the first stage aftof the combustor section 26, are allocated the highest amount of coolingair (referred to as the cooling air budget). Later stages of vanes,blade outer air seals, and other turbine engine components that arefurther downstream are provided a limited cooling air budget, relativeto the cooling air budget of the first stage vane.

While film cooling is frequently employed as a cooling method, filmcooling produces a significant drop in coolant pressure at the filmcooling holes. In a vane, or other turbine engine component, having alimited cooling air budget, the resultant pressure drop can reduce theability to provide internal cooling downstream of the film coolingholes.

With continued reference to FIG. 1, FIG. 2 illustrates an exemplaryturbine second stage blade 100. The turbine second stage blade 100includes a blade portion 110 extending from a platform 120 into theprimary flow path of the gas turbine engine 20. A root portion 130 isreceived in the gas turbine engine static support structure, andmaintains the turbine second stage blade 100 in position. The bladeportion 110 has a forward edge, referred to as a leading edge 112, andan aft edge, referred to as a trailing edge 114. A cross section A-A ofthe blade portion 110 drawn from the leading edge 112 to the trailingedge 114 has an airfoil shaped profile (illustrated in FIGS. 3 and 4)with a suction surface 116 and a pressure surface 118 connecting theleading edge 112 to the trailing edge 114.

Included within the blade portion 110 are multiple radially alignedinternal cooling passages 210 (illustrated in FIGS. 3 and 4). Theradially aligned internal cooling passages 210 form an internal coolingair flow path. Along one surface of the blade portion 110, such as thepressure surface 118, is an axially aligned skin core passage. Theaxially aligned skin core passage defines an axial flow path, and passescooling air internally along the surface 118, thereby cooling thesurface 118. Cooling air entering the axially aligned skin core passageexits the blade portion 110 through slots 119 in the trailing edge 114.In some example embodiments additional openings connect the axiallyaligned skin core passage to a radially outward surface of the tipportion 109. In such examples, a small portion of the air passingthrough the axially aligned skin core passage exits through theopenings. The small portion of the air passing through the axiallyaligned skin core passage that exits through the openings can is lessthan 20% of the air in some examples, and less than 5% of the air insome examples. In alternative examples, the slots 119 can be replacedwith multiple holes, or a single slot extending the full radial heightof the axially aligned skin core passage.

In some examples, the blade 100, illustrated in FIG. 2, is createdutilizing an investment casting process. In alternative examples, thesecond stage blade 100 can be created using a process other thaninvestment casting. In either case, the blade 100 is cast around a coredefining a negative image of the internal cooling passages of the blade100. The core is then removed from the component leaving the coolingpassages empty of any solid material. A skin core passage, such as theabove described skin core passage, is a passage formed around a thinsheet of material that conforms with the shape of the surface alongwhich the skin core passage extends. In the example of FIG. 2, the bladeportion 110 is formed around the thin sheet of material, and the thinsheet is removed from the formed blade portion 110 once the second stageblade 100 has been cast. The result is a thin passage that extends alongthe surface to which the skin core passage is adjacent. Cooling airpassing through the skin core passage 220 absorbs heat from the surfacevia convection, allowing for the surface to be actively cooled.

In some examples, an axially aligned skin core passage, such as isdescribed above, can be utilized in conjunction with a cooling flow thathas sufficient cooling air budget for film cooling upstream of theaxially aligned skin core, or in a turbine engine component thatutilizes multiple cooling air flow paths through the turbine enginecomponent where one of the cooling air flow paths has sufficient budgetfor film cooling, but the cooling air flow path feeding the axiallyaligned skin core passage lacks sufficient budget. In such an example,it can be beneficial to provide film cooling from the cooling air flowpath, or the upstream portion of the cooling air flow path, where thereis sufficient cooling air budget. However, inclusion of the axiallyaligned skin core passage prevents a direct film cooling hole betweenthe higher pressure feed cavity, 210 and the surface of the turbineengine component, 118.

With continued reference to FIGS. 1 and 2, FIG. 3 illustrates one suchturbine engine component 200. The turbine engine component 200 includesa blade portion 210 extending from a platform 220 into the primary flowpath of the gas turbine engine 20. A root portion 230 is received in thegas turbine engine static support structure, and maintains the turbineengine component 200 in position. The blade portion 210 has a forwardedge, referred to as a leading edge 212, and an aft edge, referred to asa trailing edge 214. A cross section A-A of the blade portion 210 drawnfrom the leading edge 212 to the trailing edge 214 has an airfoil shapedprofile with a suction surface 216 and a pressure surface 218 connectingthe leading edge 212 to the trailing edge 214.

Included within the blade portion 210 are multiple radially alignedcooling passages 240. The radially aligned cooling passages 240 form oneor more internal cooling air flow paths. Extending along one surface,such as the pressure surface 118, is an axially aligned skin corepassage 250. The axially aligned skin core passage 250 defines an axialflow path, and passes the cooing air internally along the correspondingsurface 118, thereby cooling the surface 118. Cooling air entering theaxially aligned skin core passage 250 exits the blade portion 210through slots 219 in the trailing edge 214. In alternative examples, theslots 219 can be replaced with multiple holes, or a single slotextending the full radial height of the axially aligned skin corepassage 250.

In order to provide film cooling to the surface 218 being cooled by theaxially aligned skin core passage 250, film cooling holes 260 areconnected to an upstream cooling passage 240 in the cooling flow paththrough multiple pedestals 262. Each pedestal 262 is a portion of theblade that interrupts (protrudes through) the axially aligned skin corepassage 250. In the illustrated example of FIG. 3, each pedestal 262includes a film cooling hole 260 connecting the surface 218 adjacent tothe axially aligned skin core passage 250 to the upstream coolingpassage 240. Cooling air is passed from the upstream cooling passage 240out the film cooling holes 260 and generates a film cooling layer alongthe aft portion of the blade 200 according to known film coolingprinciples.

With continued reference to FIG. 3, FIG. 4 illustrates a cross sectionalview of the turbine engine component 200 of FIG. 3 drawn along line B-B.In addition to the previously described internal cooling passages 240,one or more radially aligned skin core passages 270 are disposed alongthe suction side 116 of the blade 200. The radially aligned skin corepassages 270 interconnect with one or more of the cooling passages 240to form sections of the cooling flow path.

As illustrated in the cross sectional view, the pedestals 262 connectinternal walls defining the internal flow paths 240 to the exteriorsurface. In cast rotor blades, such as blades cast around a refractorymetal core or a ceramic core, the pedestals are formed utilizing voidsin the core element and are an integral structure to the blade 200. Oncethe blade 200 is cast, film cooling holes 260 are drilled into thepedestal 262 connecting the internal cooling passage 240 to the surfacebeing film cooled.

In the illustrated example of FIGS. 4, the internal cooling passages 240are fed from a single cooling air source, and form a single cooling airflow path. In alternate examples, the cooling air passages 240 canreceive air from two or more cooling air sources. In such an example,some of the cooling air passages 240 form a cooling air flow path withsufficient pressure to generate a film cooling flow path, and some ofthe cooling air passages 240 form a second cooling air flow path at alower pressure. The axially aligned skin core passage 250 is connectedto a cooling passage 240 in the lower pressure cooling air flow path,and the film cooling holes connect the higher pressure cooling air flowpath to the film cooled surface 218.

In the illustrated example of FIG. 3, the pedestals 262 have an oblongshape with a longest diameter aligned with a radius of the gas turbineengine including the blade 200. Such a shape/orientation slows downcooling air passing through the axially aligned skin core passage 250.

FIGS. 5A-5C illustrate alternative examples of the turbine enginecomponent of FIGS. 3 utilizing different shaped pedestals 262. FIG. 5Autilizes oblong oval shaped pedestals 262 with the longer diameteraligned with the axial flow direction of the gas turbine engineincluding the blade 200. One of skill in the art, having the benefit ofthis disclosure, will understand that the more the longest diameter ofthe pedestal 262 is aligned with the axial direction of the gas turbineengine, the less the pedestal 262 will obstruct flow through the skincore passage 250. Further, the optimal angle of the longest diameter,relative to an axis defined by the gas turbine engine can be determinedby one of skill in the art, having the benefit of the above disclosure.

Alternative examples, such as those illustrated in FIGS. 5B and 5C canutilize alternative pedestal 260 cross sectional geometries including,but not limited to, triangular shaped pedestals 260 (FIG. 5B), andrhombus shaped pedestals 260 (FIG. 5C). The particular shape and designof the pedestals 260 can be selected by one of skill in the art toaccount for, and control, cooling air flow through the skin core passage250, as well as to ensure adequate structural support for the internalwalls of the blade 200.

Further, with reference to FIGS. 2-5C, one of skill in the art, havingthe benefit of this disclosure, will appreciate that the axially alignedskin core passage having an outlet at the aft edge of a gas turbineengine component can be combined with the pedestal film cooling holearrangement of FIGS. 3-5C to simultaneously achieve the benefits of eachfeature

While described above with regards to blades in general, and a secondstage blade in a turbine section of a gas turbine engine in particular,one of skill in the art having the benefit of this disclosure willunderstand that the above described skin core cooling passage andpedestal arrangement can be applied to any number of actively cooledturbine engine components including, vanes, blades, blade outer airseals, and the like.

By way of example, FIG. 6 illustrates a side view of a Blade Outer AirSeal (BOAS) incorporating an axially aligned skin core cooling passage310. The BOAS 300 includes at least one internal cooling passage 320that receives cooling air from a cooling air inlet 330. In theillustrated example, the cooling air inlet 330 is at a radially outwardedge of the BOAS 300. In alternative examples, the inlet 330 can bepositioned at an fore edge 340, an aft edge 342 or a circumferentialedge 344, depending on the design constraints of the BOAS 300.

Also included within the BOAS 300 is an inlet 312 feeding an axialaligned skin core 310. Cooling air passing through the axially alignedskin core 310 exits the skin core 310 at an outlet 314 on the aft edgeof the BOAS 300. While the cooling air provided through the skin core310 is insufficient to provide film cooling, cooling air passing throughthe at least one internal cooling passage 320 has sufficient pressure.In order to provide film cooling to a radially inward surface 350 of theBOAS 300, pedestals 360 pass through the skin core 310 in the samemanner as the pedestals described above with regards to FIGS. 3-5C. Eachof the pedestals 360 includes a corresponding film cooling hole 362connecting the internal cooling passage 320 to the radially inwardsurface 350, and providing for the film cooling effect.

It is further understood that any of the above described concepts can beused alone or in combination with any or all of the other abovedescribed concepts. Although an embodiment of this invention has beendisclosed, a worker of ordinary skill in this art would recognize thatcertain modifications would come within the scope of this invention. Forthat reason, the following claims should be studied to determine thetrue scope and content of this invention.

1. A turbine engine component comprising: a fore edge connected to anaft edge via a first surface and a second surface; a plurality ofcooling passages defined within the turbine engine component; a skincore passage defined immediately adjacent said first surface; and atleast one pedestal interrupting a flow path through said skin corepassage.
 2. The turbine engine component of claim 1, wherein said atleast one pedestal comprises a plurality of pedestals distributedthrough said skin core passage.
 3. The turbine engine component of claim2, wherein at least one pedestal in said plurality of pedestals includesa film cooling hole defined at least partially within the pedestal, thefilm cooling hole connecting one of said plurality of cooling passagesto said first surface.
 4. The turbine engine component of claim 1,wherein said at least one pedestal has an oblong cross section relativeto a turbine engine including the turbine engine component.
 5. Theturbine engine of claim 4, wherein each of said oblong cross sectionsincludes a longest diameter, and said longest diameter is aligned withan axis of the turbine engine.
 6. The turbine engine of claim 4, whereineach of said oblong cross sections includes a longest diameter, and saidlongest diameter is aligned with a radius of the turbine engine.
 7. Theturbine engine of claim 1, wherein each of said pedestals has a crosssection along a direction of flow through the skin core passage, thecross section being one of an oval, a triangle, a rhombus, an airfoil,and a circle.
 8. The turbine engine of claim 1, wherein at least 80% ofa coolant entering said skin core passage exits said skin core passageat the aft edge.
 9. The turbine engine of claim 8, wherein the skin corepassage defines an axial coolant flow path.
 10. The turbine enginecomponent of claim 1, wherein said film cooling hole connects a firstcooling air flow path internal to said turbine engine component to saidfirst surface, and wherein said skin core passage receives cooling airfrom a second cooling air flow path internal to said turbine enginecomponent, and wherein said second cooling air flow path is a lowpressure cooling air flow path relative to said first cooling air flowpath.
 11. The turbine engine component of claim 1, wherein said one ofsaid plurality of cooling passages connected to said first surface viasaid cooling hole has a higher cooling air pressure than a cooling airpressure of said skin core passage.
 12. The turbine engine of claim 1,wherein the turbine engine component is one of a blade outer air seal, acombustor liner, a blade, and a vane.
 13. The turbine engine componentof claim 12, wherein the blade is a blade in a second or later turbinestage.
 14. A gas turbine engine comprising: a compressor section; acombustor section fluidly connected to the compressor section by aflowpath; a turbine section fluidly connected to the combustor sectionby the flowpath; at least one gas turbine engine component exposed to afluid passing through said flowpath, the at least one gas turbine enginecomponent including: a first surface and a second surface; at least onecooling passage defined within the turbine engine component; a skin corepassage defined immediately adjacent said first surface; and at leastone pedestal interrupting a flow path through said skin core passage,the at least one pedestal connecting an interior surface of said atleast one cooling passage to said first surface.
 15. The gas turbineengine of claim 14, further comprising a film cooling hole definedwithin said at least one pedestal, the film cooling hole providing aflow path between said at least one cooling passage to said firstsurface.
 16. The gas turbine engine of claim 14, wherein the at leastone cooling passage includes a first cooling passage and a secondcooling passage, and the at least one pedestal connects an interiorsurface of the first cooling passage to said first surface.
 17. The gasturbine engine of claim 16, wherein the first cooling passage receivescooling air from a first source, the second cooling passage receivescooling air from a second source, and wherein the skin core passagereceives cooling air from the second cooling passage.
 18. The gasturbine engine of claim 16, wherein the first cooling passage receivescooling air from a first source, the second cooling passage receivescooling air from the first cooling passage, and the skin core passagereceives cooling air from the second cooling passage.
 19. A method forcooling a gas turbine engine component comprising: passing a coolingflow along a surface of the gas turbine engine component through a skincore passage; and providing a cooling film along said surface through atleast one cooling hole, the at least one cooling hole passing through apedestal interrupting cooling flow through said skin core passage. 20.The method of claim 19, wherein providing a cooling film along saidsurface through the at least one cooling hole comprises receiving air ata first end of the cooling hole from a cooling passage internal to thegas turbine engine component and passing the air to a second end of thecooling hole at an exterior surface of the gas turbine engine component.